/* ==========================================================================
   Button Components - BEM Naming
   ========================================================================== */

/* ========================================================================
   Base Button - FastRetro Neo-Brutalist Style
   ======================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 0.625rem 1rem;
  border-radius: var(--radius-retro);
  border: var(--border-retro) solid var(--color-shadow-light);
  background-color: var(--color-surface-solid);
  color: var(--color-ink);
  font-family: inherit;
  font-size: var(--text-sm);
  font-weight: var(--font-bold);
  line-height: 1;
  text-decoration: none;
  cursor: pointer;
  box-shadow: var(--shadow-retro) var(--color-shadow-light);
  transition: transform 0.12s ease, box-shadow 0.12s ease, background-color 0.15s ease;
  white-space: nowrap;
}

.btn:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-retro-lg) var(--color-shadow-light);
}

.btn:active {
  transform: translate(2px, 2px);
  box-shadow: var(--shadow-retro-xs) var(--color-shadow-light);
}

.btn:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.btn:disabled,
.btn[disabled] {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

.btn:disabled:hover,
.btn[disabled]:hover {
  box-shadow: var(--shadow-retro) var(--color-shadow-light);
  transform: none;
}

/* Dark mode button base - VISIBLE colored shadows */
.dark .btn,
html.dark .btn {
  border-color: var(--color-border-dark-default);
  box-shadow: var(--shadow-retro) var(--color-shadow-dark-default);
}

.dark .btn:hover,
html.dark .btn:hover {
  box-shadow: var(--shadow-retro-lg) var(--color-shadow-dark-default);
}

.dark .btn:active,
html.dark .btn:active {
  box-shadow: var(--shadow-retro-xs) var(--color-shadow-dark-default);
}

/* ========================================================================
   Button Variants
   ======================================================================== */

/* Primary - FastRetro Rainbow Gradient */
.btn--primary {
  background: var(--gradient-retro-rainbow);
  color: var(--color-shadow-light);
  border-color: var(--color-shadow-light);
}

.dark .btn--primary,
html.dark .btn--primary {
  background: linear-gradient(90deg, oklch(75% 0.14 95), oklch(70% 0.16 350), oklch(70% 0.12 230));
  color: oklch(15% 0.02 260);
  border-color: var(--color-border-dark-pink);
  box-shadow: var(--shadow-retro) var(--color-shadow-dark-pink);
}

.btn--primary:hover {
  box-shadow: var(--shadow-retro-lg) var(--color-shadow-light);
}

.dark .btn--primary:hover,
html.dark .btn--primary:hover {
  box-shadow: var(--shadow-retro-lg) var(--color-shadow-dark-pink);
}

/* Secondary - Sky/Pastel Blue */
.btn--secondary {
  background: linear-gradient(90deg, var(--color-pastel-blue), var(--color-pastel-lavender));
  color: var(--color-shadow-light);
  border-color: var(--color-shadow-light);
}

.dark .btn--secondary,
html.dark .btn--secondary {
  background: linear-gradient(90deg, oklch(55% 0.12 230), oklch(55% 0.12 285));
  color: oklch(95% 0.02 230);
  border-color: var(--color-border-dark-sky);
  box-shadow: var(--shadow-retro) var(--color-shadow-dark-sky);
}

.btn--secondary:hover {
  box-shadow: var(--shadow-retro-lg) var(--color-shadow-light);
}

.dark .btn--secondary:hover,
html.dark .btn--secondary:hover {
  box-shadow: var(--shadow-retro-lg) var(--color-shadow-dark-sky);
}

/* Ghost - Subtle with FastRetro shadow */
.btn--ghost {
  background-color: oklch(98% 0.01 0);
  color: var(--color-gray-700);
  border-color: var(--color-shadow-light);
  box-shadow: var(--shadow-retro-sm) var(--color-shadow-light);
}

.btn--ghost:hover {
  background-color: var(--color-pastel-cream);
  box-shadow: var(--shadow-retro) var(--color-shadow-light);
}

.dark .btn--ghost,
html.dark .btn--ghost {
  background-color: oklch(22% 0.02 260);
  color: var(--color-gray-200);
  border-color: var(--color-border-dark-default);
  box-shadow: var(--shadow-retro-sm) var(--color-shadow-dark-default);
}

.dark .btn--ghost:hover,
html.dark .btn--ghost:hover {
  background-color: oklch(28% 0.03 260);
  box-shadow: var(--shadow-retro) var(--color-shadow-dark-default);
}

/* Danger/Negative - Red with FastRetro */
.btn--danger,
.btn--negative {
  background: linear-gradient(90deg, oklch(75% 0.16 30), oklch(65% 0.18 25));
  color: var(--color-shadow-light);
  border-color: var(--color-shadow-light);
}

.dark .btn--danger,
.dark .btn--negative,
html.dark .btn--danger,
html.dark .btn--negative {
  background: linear-gradient(90deg, oklch(55% 0.18 25), oklch(50% 0.18 25));
  color: oklch(95% 0.02 25);
  border-color: oklch(70% 0.2 25);
  box-shadow: var(--shadow-retro) oklch(55% 0.2 25);
}

/* Success/Positive - Green with FastRetro */
.btn--success,
.btn--positive {
  background: linear-gradient(90deg, var(--color-pastel-mint), oklch(80% 0.1 145));
  color: var(--color-shadow-light);
  border-color: var(--color-shadow-light);
}

.dark .btn--success,
.dark .btn--positive,
html.dark .btn--success,
html.dark .btn--positive {
  background: linear-gradient(90deg, oklch(50% 0.14 145), oklch(45% 0.14 145));
  color: oklch(95% 0.02 145);
  border-color: oklch(65% 0.16 145);
  box-shadow: var(--shadow-retro) oklch(50% 0.16 145);
}

/* ========================================================================
   Button Sizes
   ======================================================================== */

/* Small */
.btn--sm {
  padding: 0.375rem 0.75rem;
  font-size: var(--text-xs);
  border-radius: var(--radius-lg);
}

/* Large */
.btn--lg {
  padding: 0.875rem 1.5rem;
  font-size: var(--text-base);
  border-radius: var(--radius-2xl);
}

/* ========================================================================
   Button Shapes
   ======================================================================== */

/* Circle/Icon button */
.btn--circle {
  width: 2.5rem;
  height: 2.5rem;
  padding: 0;
  border-radius: var(--radius-full);
}

.btn--circle.btn--sm {
  width: 2rem;
  height: 2rem;
}

.btn--circle.btn--lg {
  width: 3rem;
  height: 3rem;
}

/* Full width */
.btn--block {
  display: flex;
  width: 100%;
}

/* ========================================================================
   Button States
   ======================================================================== */

/* Loading state */
.btn--loading {
  position: relative;
  color: transparent;
  pointer-events: none;
}

.btn--loading::after {
  content: '';
  position: absolute;
  width: 1rem;
  height: 1rem;
  border: 2px solid currentColor;
  border-right-color: transparent;
  border-radius: var(--radius-full);
  animation: spin 0.75s linear infinite;
}

/* Icon only (for accessibility) */
.btn--icon-only {
  padding: 0.5rem;
}

/* ========================================================================
   Button Groups
   ======================================================================== */
.btn-group {
  display: inline-flex;
  gap: 0;
}

.btn-group .btn {
  border-radius: 0;
}

.btn-group .btn:first-child {
  border-radius: var(--radius-xl) 0 0 var(--radius-xl);
}

.btn-group .btn:last-child {
  border-radius: 0 var(--radius-xl) var(--radius-xl) 0;
}

.btn-group .btn:not(:last-child) {
  border-right-width: 1px;
}

/* ========================================================================
   Link styled as button
   ======================================================================== */
a.btn {
  text-decoration: none;
}

a.btn:hover {
  text-decoration: none;
}

/* ========================================================================
   Responsive
   ======================================================================== */
@media (min-width: 640px) {
  .sm\:btn--lg {
    padding: 0.875rem 1.5rem;
    font-size: var(--text-base);
  }
}

/* ========================================================================
   Legacy Aliases (Tailwind-style class names)
   For backward compatibility with existing views
   ======================================================================== */

/* btn-modern = btn (FastRetro style) */
.btn-modern {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 0.625rem 1rem;
  border-radius: var(--radius-retro);
  border: var(--border-retro) solid var(--color-shadow-light);
  background-color: var(--color-surface-solid);
  color: var(--color-ink);
  font-family: inherit;
  font-size: var(--text-sm);
  font-weight: var(--font-bold);
  line-height: 1;
  text-decoration: none;
  cursor: pointer;
  box-shadow: var(--shadow-retro) var(--color-shadow-light);
  transition: transform 0.12s ease, box-shadow 0.12s ease;
  white-space: nowrap;
}

.btn-modern:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-retro-lg) var(--color-shadow-light);
}

.btn-modern:active {
  transform: translate(2px, 2px);
  box-shadow: var(--shadow-retro-xs) var(--color-shadow-light);
}

/* btn-primary (FastRetro style) */
.btn-primary {
  background: var(--gradient-retro-rainbow);
  color: var(--color-shadow-light);
  border-color: var(--color-shadow-light);
}

.dark .btn-primary,
html.dark .btn-primary {
  background: linear-gradient(90deg, oklch(75% 0.14 95), oklch(70% 0.16 350), oklch(70% 0.12 230));
  color: oklch(15% 0.02 260);
  border-color: var(--color-border-dark-pink);
  box-shadow: var(--shadow-retro) var(--color-shadow-dark-pink);
}

/* btn-secondary (FastRetro style) */
.btn-secondary {
  background: linear-gradient(90deg, var(--color-pastel-blue), var(--color-pastel-lavender));
  color: var(--color-shadow-light);
  border-color: var(--color-shadow-light);
}

.dark .btn-secondary,
html.dark .btn-secondary {
  background: linear-gradient(90deg, oklch(55% 0.12 230), oklch(55% 0.12 285));
  color: oklch(95% 0.02 230);
  border-color: var(--color-border-dark-sky);
  box-shadow: var(--shadow-retro) var(--color-shadow-dark-sky);
}

/* btn-ghost (FastRetro style) */
.btn-ghost {
  background-color: oklch(98% 0.01 0);
  color: var(--color-gray-700);
  border-color: var(--color-shadow-light);
  box-shadow: var(--shadow-retro-sm) var(--color-shadow-light);
}

.dark .btn-ghost,
html.dark .btn-ghost {
  background-color: oklch(22% 0.02 260);
  color: var(--color-gray-200);
  border-color: var(--color-border-dark-default);
  box-shadow: var(--shadow-retro-sm) var(--color-shadow-dark-default);
}

.btn-ghost:hover {
  background-color: var(--color-pastel-cream);
  box-shadow: var(--shadow-retro) var(--color-shadow-light);
}

.dark .btn-ghost:hover,
html.dark .btn-ghost:hover {
  background-color: oklch(28% 0.03 260);
  box-shadow: var(--shadow-retro) var(--color-shadow-dark-default);
}